Valve plate for reciprocating compressor

ABSTRACT

A valve plate for a reciprocating compressor including first and second members joined together in spaced apart relation, the first member having a plurality of substantially cylindrical pins extending normal to a first surface thereof, the second member being joined to the top of the cylindrical pins, the first and second members defining therebetween a first radially extending flow path. The second member includes a first portion extending normal to a first surface thereof. The first portion of the second member is spaced apart from an inner edge of the first member to define a second flow path for the gas, the second flow path being normal to the first flow path, and being an uninterrupted continuation thereof. The gas passing through the radially extending flow path impinges upon a curved surface defined by the junction of the first surface and the first portion of the second member, to thence be directed through the second flow path.

United States Patent Kropiwnicki [451 Feb. 11, 1975 VALVE PLATE FOR RECIPROCATING COMPRESSOR [75] Inventor: Tadek M. Kropiwnicki, Syracuse,

[73] Assignee: Carrier Corp., Syracuse, NY.

[22] Filed: June 4, 1973 [21] Appl. No.: 366,911

[51] Int. Cl. F04b 39/10 [58] Field of Search 251/367; 137/512.15; 138/37; 417/563, 564, 567

[56] References Cited UNITED STATES PATENTS 1,938,218 12/1938 Dempsey, Jr. 417/563 X 2,682,280 6/1954 Nicklas l37/5l2.l5

2,935,248 5/1960 Gerteis l37/5l2.l5 X

3,050,237 8/1962 Nicholas 417/564 3,066,856 12/1962 Frank l37/5l2.l5 X

Primary ExaminerCharles J. Myhre Assistant Examiner-Ira S. Lazarus Attorney, Agent, or Firm.l. Raymond Curtin; Barry 57 ABSTRACT A valve plate for a reciprocating compressor including first and second members joined together in spaced apart relation, the first member having a plurality of substantially cylindrical pins extending normal to a first surface thereof, the second member being joined to the top of the cylindrical pins, the first and second members defining therebetween a first radially extending flow path. The second member includes a first portion extending normal to a first surface thereof. The first portion of the second member is spaced apart from an inner edge of the first member to define a second flow path for the gas, the second flow path being normal to the first flow path, and being an uninterrupted continuation thereof. The gas passing through the radially extending flow path impinges upon a curved surface defined by the junction of the first surface and the first portion of the second member, to thence be directed through the second flow path.

11 Claims, 4 Drawing Figures 2 27' J27 V ///////////////////I 24 29 2' I 26 m s 22 30 l7 i Z 20 PATENTEDFEBI 1 I975 865,345

SHEET 2 [1F 2 VALVE PLATE FOR RECIPROCATING COMPRESSOR BACKGROUND OF THE INVENTION This invention relates to reciprocating compressors, and more particularly, to valve plates employed in such compressors.

The utilization of hermetically sealed compressors in mechanical refrigeration units has become increasingly prevalent throughout the refrigeration industry. Various compressor configurations have been designed and developed by the many manufacturers of such compressors. In recent years, the trend in the design of hermetically sealed compressors has been to make such compressors as compact as possible, thus not only reducing the size of such compressors, but also lowering the cost of manufacturing same.

In many contemporary compressor designs, a suction gas manifold is disposed within hermetically sealed shells of the compressor, transversely to the cylinders thereof. Thus, the suction gas, which generally passes downwardly over the windings of the compressor motor to cool same and thence is accumulated in the suction gas manifold, must undergo approximately a 90 change in flow direction in order to be introduced into the top of the cylinders of the compressor as is most desirable for optimum performance efficiency. Very often, such change in direction of the gas flow occurs in the valve plate of the compressor.

Heretofore, valve plates available in the prior art have caused pressure losses, turbulence, and an overall reduction in the operating performance and efficiency of the compressors when utilized as the means for changing the direction of fiow of the gas. As is obvious, it is highly desirable to provide a valve plate, that, not only functions to change the direction of the gas flow, but also avoidsthe introduction of problems caused by valve plates of the prior art.

SUMMARY OF THE INVENTION It is therefore an object of the invention to provide a novel valve plate suitable for use in hermetically sealed compressors.

It is a further object of the present invention to provide a valve plate wherein the gas flowing therethrough undergoes a substantially 90 change in direction.

It is yet another object of the invention to provide a valve plate wherein the gas flowing therethrough undergoes a change of approximately 90 in its direction of flow, yet minimal turbulence and pressure losses occur as a result of such change in direction.

These and other objects in the present invention are obtained by providing a valve plate having a first member having a plurality of upstanding members extending normal to a first surface thereof. The valve plate includes a second member having a first surface which is connected to the top of the upstanding members, the respective surfaces of the first and second members thus being maintained in spaced apart relationship to define therebetween a first radially extending flow path for the gas. The second member further includes a first portion integrally connected to the first surface and extending substantially normal thereto. The first portion is in spaced relationship to an inboard edge of the first member to define therebetween a second longitudinally extending flow path for the gas, the second flow path being substantially normal to, and being a continuous, uninterrupted extension of, the first flow path. The direction of flowv of the gas is changed by approximately by contacting the surface defining the junction of the first portion of the second member and the first surface thereof, the gas thus passing from the first flow path into the second flow path. The gas thereafter is introduced into the cylinder of the compressor, the flow thereof being regulated by the suction valve.

In a preferred embodiment, the junction of the first surface and the first portion of the second member defines a curved surface. The gas flowing in the radially extending flow path contacts the curved surface and has its direction of flow changed by approximately 90 as a result of its impingement against the curved surface.

Further details and features of the present invention shall be more clearly understood by reference to the accompanying figures of the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates a longitudinal, sectional view, taken I along line I---[ of FIG. 2, ofa valve plate in accordance with the present invention as embodied within a typical compressor;

FIG. 2 illustrates a horizontal sectional view of a portion ofa compressor, taken along line II-II of FIG. 1, and having a portion thereof broken away for purposes of clarity;

FIG. 3 illustrates a fragmentary perspective view of a valve plate in accordance with the prior art; and

FIG. 4 illustrates an exploded perspective view of the valve plate in a valve plate assembly including suction and discharge valves and guides.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1 and 2 of the drawings, there is illustrated a portion of a reciprocating compressor in which the valve plate in accordance with the present invention is embodied. In referring to the various Figures of the drawings, like numerals shall refer to like parts.

The compressor 10 includes a cast cylinder block 11 having walls 12 which define a cylinder 13. As shown in FIG. I, a piston 14 is suitably disposed within cylinder l3. Piston 14 is connected via connecting rod 15 to a crankshaft (not shown) of the compressor. Rotation of the crankshaft will cause the piston to reciprocate in the cylinder to compress gas drawn thereinto. As shown in FIG. I, the cylinder has at its outer end, a shoulder 16 on which the valve assembly including the valve plate of the present invention is supported.

The valve assembly includes a guide 17 whichis directly supported on shoulder 16 of the cylinder. Suction valve 18 is suitably positioned on and supported by guide 17. Suction valve 18, as shown in FIG. 4, includes outwardly extending ear portions 18 which are adapted to directly rest on a supporting surface of guide 17. Suction valve 18 is lifted off its seat during the suction stroke of piston 14 to admit gas into cylinder 13.

The valve assembly further includes valve plate 19, which shall be described in more detail hereinafter. Discharge valve 24 is provided to regulate the flow of compressed gas from the cylinder. The discharge valve is suitably guided and supported by discharge valve guide 26. An annular disk is suitably connected to guide 26 by means such as nut 27 and bolt 27'. Disk 25', in combination with the top surface of the valve plate, define a seat for discharge valve 24'.

A cylinder head 28, having an annular chamber 28 provided for receiving discharge gas, is suitably attached, by means not shown, such as screws or bolts, to the cylinder block I1.

As shown particularly in FIG. 2, a bearing cap 30 is suitably connected to and supported on the top surface of cylinder block 11. Bearing cap 30 has ports 34 provided in its lower surface. Ports 34 communicate with ports 32 which are provided in a top surface of the cylinder block for a reason that shall be more fully explained hereinafter. End turns 31 of a motor are provided in a chamber defined by the outer wall of bearing cap 30, the chamber also functioning as a suction gas manifold.

In operation, gas to be compressed is drawn into the hermetic shell of the compressor and flows downwardly over the motor windings to cool the same in a manner well known to those skilled in the art. The arrows shown in FIG. 2 indicate the flow path of the refrigerant gas. The gas after having passed over the motor windings is collected in the chamber defined by the outer walls of bearing cap 30. The gas then passes through ports 34 in the lower wall of bearing cap 30 and flows, via communicating ports 32, into suction chambers 33 defined by wall portions of the cylinder block.

As is best shown in FIG. 2, cylinder 13 is positioned transversely to the general direction of flow of the gas. Thus, it is necessary for the gas to undergo substantially a 90 change in direction so as to be emitted at the top of the cylinder as is desired for maximum operating efficiency. The gas undergoes the change in the direction of its flow as it passes through the valve plate.

FIG. 3 shows a valve plate of the prior art which has heretofore been utilized in refrigerant compressors of the type described above.

The valve plate 35 of the prior art is essentially formed from a unitary piece of roll stock. Radially extending holes 36 are drilled about the outer circumference of the valve plate to provide radially extending flow paths for the gas. As is obvious, holes 36 are generally of a small diameter. Valve plate 35 further includes downwardly extending portions 37 and 39 which define therebetween an annular slot 38, the slot being formed by a suitable machining process in the lower surface of the valve plate. Slot 38 communicates with the radially extending holes to form a second flow path for the gas, the second flow path being substantially normal to the first flow path. Refrigerant gas from a suction manifold, flows radially inward through the holes and impinges upon the inner surface of downwardly extending portion 37. The impingement of the gas on such surface creates an extreme amount of turbulence due to the manner in which the gas deflects and reflects therefrom. The gas eventually flows downwardly through the second flow path provided by slot 38. Slot 38 has a suitable suction valve positioned thereover which functions to regulate the flow of gas therefrom into the cylinder of the refrigerant gas compressor.

example, holes 36 and slot 38 are of relatively narrow width. The narrow width of such openings generally restricts the flow of gas through the valve plate so as to cause pressure losses, thus decreasing the operating performance of the compressor. In addition, the manner in which the gas flowing through the radially extending holes 36 impinges upon the inner surface of downwardly extending portion 37 causes turbulence which again restricts the flow of gas through the valve plate. As is most manifest, it would be highly advantageous to provide a valve plate eliminating the problems of the valve plate illustrated in FIG. 3. However, such valve plate must function to change the direction of flow of gas substantially Valve plate 19 of the instant invention accomplishes the foregoing.

Valve plate 19 includes a first member 20 preferably having a plurality of upstanding members, shown as cylindrical pins 22, extending normal to a first surface thereof. The valve plate further includes a second member 21 which is suitably joined to the top of upstanding members 22. Such members may be joined by resistance welding or similar known techniques. Members 21 and 20 are thus provided in spaced apart relationship and define therebetween a first radially extending flow path 24 for gas passing through the valve plate. As is best shown in FIG. 1, member 21 includes longitudinally extending portion 23, which is provided in spaced apart relation from an inboard edge of member 20 so as to define therebetween a second longitudinally extending flow path 25 for the gas. Flow path 25 is an uninterrupted continuation of flow path 24.

In order to minimize the turbulence created by the impingement of the gas as it flows through radially extending passage 24 to thereby contact the inner surface of portion 23 so that a change of direction in the flow of gas occurs, the junction of the lower surface of member 21 and portion 23 defines a curved surface. By providing a curved surface at the foregoing junction, a minimum of turbulence will be created. Instead of providing a surface which produces an abrupt change in the flow of gas through the valve plate, as is typified by surface 38' of the valve plate illustrated in FIG. 3, the curved surface gradually alters the direction of flow of the gas, thereby minimizing the creation of turbulence.

In addition, the lower part of portion 23 flares outwardly from the inboard edge of member 20 so that the lower part of longitudinally extending flow path 25 is of increasing diameter. By increasing the diameter of the flow path, a pressure regain nozzle is created to thereby improve the overall operating performance of the compressor. Any pressure losses caused by restrictions and changes in direction of flow should by substantially recovered via the nozzle outlet from portion 25.

As noted hereinbefore in the discussion of the prior art, holes 36 are of relatively narrow diameter. With reference to FIGS. 2 and 4, it can be clearly observed that upstanding cylindrical members 22 are spaced rather far apart to provide therebetween relatively wide mouth inlets for the passage of gas through radially extending flow path 24. Preferably, adjacent cylindrical members 22 are spaced apart so that they define there between, in combination with the opposed surfaces of members 20 and 21 radially extending openings of approximately 40. The relatively wide openings minimize pressure losses provided as a result of the passage of gas through the valve plate. Thus, as is readily apparent,

the valve plate of the present invention substantially improves over the valve plate of the prior art, as typified by the valve plate illustrated in FlG. 3.

With reference to FIG. 2, it should be observed that the gas passes from the annular suction chamber defined by the walls of bearing cap 30 through ports 32 and 34 into chamber 33 provided about cylinder 13. The gas then flows radially inward through flow path 24 defined between the planar members and 21 and thence passes downwardly through the second flow path 25. The gas then enters the cylinder under the control of valve 18.

While a preferred embodiment of the present invention has been described and illustrated, the present invention should not be limited thereto, but may be otherwise embodied within the scope of the following claims.

I claim:

1. A valve plate for use in a reciprocating gas compressor comprising:

a. a first member having a plurality of upstanding members extending normal to a first surface thereof; and

b. a second member having a first surface connected to the top of said upstanding members, said respective surfaces of said first and second members being maintained in spaced relationship to define therebetween a first radially extending flow path for said gas, said second member including a first portion integrally connected to said first surface, extending substantially normal thereto, and being in spaced relationship to an inboard edge of said first member to define therebetween a second longitudinally extending flow path for said gas, the direction of flow of said gas being changed by approximately 90 by contacting the surface defining the junction of said first portion of said second member and said first surface thereof, the gas passing from said first flow path into said second flow path.

2. A valve plate in accordance with claim 1 wherein the junction of said first surface and said first portion of said second member defines a curved surface, the gas flowing in the radially extending flow path contacting said curved surface, and having its direction of flow changed by approximately 90 thereby.

3. A valve plate in accordance with claim 2 wherein the space defined by the first portion of said second member and said inboard edge of said first member is of increasing width from the top to the bottom thereof. 7 4. A valve plate in accordance with claim 1 wherein the space defined by the first portion of said second member and said inboard edge of said first member is of increasing width from the top to the bottom thereof.

5. A valve plate for use in a reciprocating gas compressor comprising:

a. a first member having a plurality of substantially cylindrical pins extending normal to a first surface thereof; and

b. a second member having a first surface connected to the top of said cylindrical pins, said respective surfaces of said first and second members being maintained in spaced relationship, said respective surfaces and adjacent pairs of said plurality of cylindrical pins defining a plurality of radially extending flow paths for the passage of said gas, said second member including a longitudinally extending and integrally formed portion extending substantially normalto said surface thereof, said first portion of said second member being spaced apart from an inboard edge of said first member to define therebetween a second flow path for said gas, said second flow path being substantially normal to said first flow path, the gas flowing through said first flow path impinging upon a substantially curved surface defined by the junction of said longitudinally extending portion of said second member and the first-surface thereof, the gas thereafter being directed through said second flow path, the curved surface minimizing the creation of turbulence caused by the change of direction in the flow of said gas to minimize pressure losses in the passage of said gas through said valve plate.

6. A valve plate in accordance with claim 5 wherein said first portion of said second member diverges from the inboard edge of said first member so the width of the second flow path is increased at its lower end.

7. A valve plate in accordance with claim 6 wherein each of said plurality of radially extending flow paths extends approximately 40 about the circumference of said first and second members.

8. A valve plate in accordance with claim 5 wherein each of said plurality of radially extending flow paths extends approximately 40 about the circumference of said first and second members.

9. A valve plate for use in a reciprocating gas compressor comprising:

a. a first member having a generally planar surface;

and

b. a second member having a generally planar surface, a plurality of upstanding members extending normal to said planar surfaces, and being connected thereto to maintain said first and second members in spaced relationship to define therebetween a first radially extending flow path for said gas, said second member including a first portion integrally connected to said generally planar surface, extending substantially normal thereto, and being in spaced relationship to an inboard edge of said first member to define therebetween a second longitudinally flow path for said gas, the direction of flow of said gas being changed by approximately by contacting the surface defining the junction of said first portion of said second member and said first surface thereof, the gas passing from said first flow path into said second flow path.

10. A valve plate in accordance with claim 9 wherein the junction of said first portion of said second member and the planar surface thereof defines a curved surface, the gas flowing in the radially extending flow path contacting the curved surface, and having its direction of flow changed by approximately 90 thereby.

11. A valve plate in accordance with claim 10 wherein the space defined by the first portion of said second member and said inboard edge of said first member is of increasing width from the top to the bot- 

1. A valve plate for use in a reciprocating gas compressor comprising: a. a first member having a pluRality of upstanding members extending normal to a first surface thereof; and b. a second member having a first surface connected to the top of said upstanding members, said respective surfaces of said first and second members being maintained in spaced relationship to define therebetween a first radially extending flow path for said gas, said second member including a first portion integrally connected to said first surface, extending substantially normal thereto, and being in spaced relationship to an inboard edge of said first member to define therebetween a second longitudinally extending flow path for said gas, the direction of flow of said gas being changed by approximately 90* by contacting the surface defining the junction of said first portion of said second member and said first surface thereof, the gas passing from said first flow path into said second flow path.
 2. A valve plate in accordance with claim 1 wherein the junction of said first surface and said first portion of said second member defines a curved surface, the gas flowing in the radially extending flow path contacting said curved surface, and having its direction of flow changed by approximately 90* thereby.
 3. A valve plate in accordance with claim 2 wherein the space defined by the first portion of said second member and said inboard edge of said first member is of increasing width from the top to the bottom thereof.
 4. A valve plate in accordance with claim 1 wherein the space defined by the first portion of said second member and said inboard edge of said first member is of increasing width from the top to the bottom thereof.
 5. A valve plate for use in a reciprocating gas compressor comprising: a. a first member having a plurality of substantially cylindrical pins extending normal to a first surface thereof; and b. a second member having a first surface connected to the top of said cylindrical pins, said respective surfaces of said first and second members being maintained in spaced relationship, said respective surfaces and adjacent pairs of said plurality of cylindrical pins defining a plurality of radially extending flow paths for the passage of said gas, said second member including a longitudinally extending and integrally formed portion extending substantially normal to said surface thereof, said first portion of said second member being spaced apart from an inboard edge of said first member to define therebetween a second flow path for said gas, said second flow path being substantially normal to said first flow path, the gas flowing through said first flow path impinging upon a substantially curved surface defined by the junction of said longitudinally extending portion of said second member and the first surface thereof, the gas thereafter being directed through said second flow path, the curved surface minimizing the creation of turbulence caused by the change of direction in the flow of said gas to minimize pressure losses in the passage of said gas through said valve plate.
 6. A valve plate in accordance with claim 5 wherein said first portion of said second member diverges from the inboard edge of said first member so the width of the second flow path is increased at its lower end.
 7. A valve plate in accordance with claim 6 wherein each of said plurality of radially extending flow paths extends approximately 40* about the circumference of said first and second members.
 8. A valve plate in accordance with claim 5 wherein each of said plurality of radially extending flow paths extends approximately 40* about the circumference of said first and second members.
 9. A valve plate for use in a reciprocating gas compressor comprising: a. a first member having a generally planar surface; and b. a second member having a generally planar surface, a plurality of upstanding members extending normal to said planar surfaces, and being connected thereto to maintain said first and second members in spaced reLationship to define therebetween a first radially extending flow path for said gas, said second member including a first portion integrally connected to said generally planar surface, extending substantially normal thereto, and being in spaced relationship to an inboard edge of said first member to define therebetween a second longitudinally flow path for said gas, the direction of flow of said gas being changed by approximately 90* by contacting the surface defining the junction of said first portion of said second member and said first surface thereof, the gas passing from said first flow path into said second flow path.
 10. A valve plate in accordance with claim 9 wherein the junction of said first portion of said second member and the planar surface thereof defines a curved surface, the gas flowing in the radially extending flow path contacting the curved surface, and having its direction of flow changed by approximately 90* thereby.
 11. A valve plate in accordance with claim 10 wherein the space defined by the first portion of said second member and said inboard edge of said first member is of increasing width from the top to the bottom thereof. 